LEDs are semiconductor devices that emit light when a voltage is applied. LEDs continue to experience an increase in market share over conventional forms of lighting and benefit from a superior lighting quality and a high energy efficiency. In many instances, LEDs are less expensive to manufacture than conventional forms of lighting, including fluorescent and incandescent lighting for example.
Existing LED systems often employ a compound lens to achieve shaping and control of emitted LED light in ways not available from single-element lenses. For example, it is known to use two or more individual lenses, physically mounted in the illumination path of the LED, to achieve the desired focus, columniation, beam spread, and shape of emitted LED light.
The resulting combination of LED light (visible and invisible to the human eye) using conventional compound lenses are necessarily mechanically and optically complex. Existing compound lens systems require costly mechanical assemblies to capture and align their multiple, individual focusing lenses. Existing compound lens systems are often inflexible (e.g., not tunable) with regard to meeting their primary design configurations. In addition, existing compound lens systems generally do not offer a method to easily modify the properties of the emitted radiation without costly ancillary mountings and focusing housings.